Rain Bringing Forth the Hundred Grains: Guyu, Civilization's Spring Rain, and the Legend of Cangjie
Drawing on pre-Qin Confucian and Daoist philosophy, etymology, astronomy, phenology, and the legend of Cangjie's invention of writing, this article offers an in-depth reading of the Guyu (Grain Rain) solar term. It examines the humane grace of Heaven and Earth embodied in "rain giving birth to the hundred grains," the firm-yet-yielding way of hexagram Guai's "resolving away the last remnant of yin," and the profound meaning behind "Heaven rained down millet, and ghosts wept in the night" at the origin of writing—returning readers to the ancient world of the unity of Heaven and humanity.

Chapter 5: The Daoist Perspective — Moistening Things in Silence and the Virtue of Non-Contention
Section 1: The Highest Good Is Like Water — The Daoist Character of Guyu's Rain
If Confucianism reads "the humaneness of Heaven and Earth" out of the rain of Guyu, then Daoism reads, from that very same rain, the character of the Dao—the highest good is like water, moistening things in silence, benefiting all without contention.
The Most High (Laozi) speaks, in Chapter 8 of the Daodejing, that eternal saying: "The highest good is like water. Water excels in benefiting the ten thousand things without contending with them, and dwells in places that people disdain—therefore it comes close to the Dao." (上善若水。水善利万物而不争,处众人之所恶,故几于道。) The highest good is like water. Water excels at nourishing the ten thousand things without contending with them, and settles in the lowly places that all people disdain—and for this reason it comes closest to the Dao.
The rain of Guyu is precisely the finest embodiment of this "highest good, like water." Observe how it "benefits the ten thousand things": with a single rain, the hundred grains are brought to life, the grasses and trees are moistened, the seedlings grow tall—it gives the vitality of life to everything between Heaven and Earth, without exception, without partiality. Observe, too, how it "does not contend": the rain nourishes and rears the ten thousand things, yet never claims credit, never demands anything in return, never contends even the slightest bit with the things it nourishes. And observe, finally, how it "dwells in places that people disdain": the rain falls, seeps into the lowest, muddiest soil, and willingly dwells in the very lowest place—while everyone else strives to rise, only water (rain) is willing to flow downward.
The Most High says that water "comes close to the Dao"—nearest of all to the Dao. Guyu's rain, then, is the rain that comes nearest of all to "the Dao." It demonstrates "benefiting the ten thousand things" through silent nourishment, demonstrates "non-contention" through quiet seeping, and demonstrates "dwelling in places that people disdain" through willing occupation of the lowly place. As the ancients gazed up at the sky and scrutinized the earth at the season of Guyu, watching the rain silently infuse each and every seedling with vitality, what they perceived was precisely this power, so near to "the Dao," that transforms all things greatly without a word.
Section 2: "Moistening Things, Fine and Silent" — A Model of Non-Action Through Which Nothing Is Left Undone
One of the core ideas of Daoist thought is "non-action, and yet nothing is left undone" (无为而无不为). What is non-action (wuwei)$33 It is not doing nothing at all, but rather not acting wantonly, not forcing action, not using human effort to distort the natural disposition of things. And what does "nothing is left undone" mean$34 Precisely because one does not act wantonly, all things are accomplished according to their own nature—and so nothing, in the end, is left unaccomplished.
The rain of Guyu is precisely the most perfect natural exemplar of "non-action, and yet nothing is left undone." It practices "non-action"—it is never deliberate, never ostentatious, chooses no particular hour, selects no particular target; it merely follows its nature of "moistening downward," falling quietly, seeping silently. And yet it also achieves "nothing left undone"—it is precisely this silent, soundless nourishment that accomplishes the grand transformation of "rain giving birth to the hundred grains"; whatever between Heaven and Earth possesses the will to live receives its grace, without exception. The rain has "deliberately" done nothing at all, and yet it has accomplished everything.
The Most High says: "The Dao constantly does nothing, and yet nothing is left undone" (道常无为而无不为) (Daodejing, Chapter 37). And also: "In the pursuit of learning, one gains daily; in the pursuit of the Dao, one loses daily. Loss upon loss, until one arrives at non-action. Non-action, and yet nothing is left undone." (Chapter 48)
This supreme wisdom, when put into words, sounds somewhat abstract, but if one simply observes quietly, at the season of Guyu, how a spring rain moistens all things, one may suddenly comprehend it—the Dao's "non-action, and yet nothing left undone" has, all along, been silently playing out above our heads and beneath our feet, every single day. The rain never convenes a council to deliberate which seedling to moisten and which to spare; it simply falls, "without action"—and it is precisely this "non-action" that brings about the "nothing left undone" of the hundred grains' birth.
Section 3: The Virtue of Non-Contention and Guyu's "Yielding"
Daoism places great weight on "non-contention." The Most High says: "It is precisely because he does not contend that no one in the world can contend with him." (Daodejing, Chapter 22) And also: "Water excels in benefiting the ten thousand things without contending with them... It is precisely because it does not contend that it incurs no blame." (Chapter 8) Non-contention is one of the highest virtues in Daoism.
The rain of Guyu enacts "non-contention" to the fullest degree. But still more thought-provoking is the fact that Guyu's very position in "late spring" is itself a kind of "yielding" born of "non-contention." By Guyu, spring has already reached its final act; it is about to yield the stage to summer. Throughout the whole of spring, sprouting diligently, blossoming, coaxing forth the hundred grains—and by Guyu, its achievement is nearly complete—yet it does not cling covetously to the stage, but calmly hands the baton of growth to the summer soon to come, and quietly exits itself. This posture of "accomplishing one's task without claiming credit for it" and "generating life without possessing it" is precisely the state that Daoism most exalts.
The Most High says: "It generates yet does not possess; it acts yet does not presume upon its own ability; it accomplishes its task yet does not dwell upon it. Precisely because it does not dwell upon it, its accomplishment never departs." (Daodejing, Chapter 2) It nurtures the ten thousand things yet does not claim them as its own possession; it acts with effect yet does not presume upon its own capability; it accomplishes its task successfully yet does not dwell proudly upon its achievement. Precisely because it does not dwell upon its achievement, that achievement, in turn, never fades away.
The spring of Guyu has nourished the hundred grains and fostered the mulberry and silk—it may indeed be said to have "accomplished its task"; and yet it turns and yields its place to summer, precisely enacting "accomplishing its task yet not dwelling upon it." This "yielding" of late spring, and the "non-contention" of the rain, resonate together, inner and outer, jointly constituting that Daoist wisdom—humble, self-effacing, and vast—that lies deep within Guyu.
Section 4: "Reversal Is the Movement of the Dao" — The Turning Point of Fullness and Emptiness Within Guyu
Daoism, in its observation of the ten thousand things, discerns one of the deepest patterns of all—"reversal is the movement of the Dao." The Most High says: "Reversal is the movement of the Dao; weakness is the function of the Dao." (Daodejing, Chapter 40) "Reversal" means returning, means the mutual generation of opposites, means that things, having reached their extreme, must turn back. When a thing develops to its utmost point, it must transform into its opposite—this is the fundamental manner in which the Dao moves.
Within Guyu lies concealed precisely this turning point of fullness and emptiness that is "reversal, the movement of the Dao." Guyu is the last solar term of spring, the moment when spring's qi is at its fullest, its most abundant—one degree fuller still, and it must "reverse," must turn into summer. This corresponds precisely to hexagram Guai, which we shall discuss at length below: five yang lines already abundant, about to resolve away the last remaining yin line and become pure yang (hexagram Qian, Start of Summer); yet immediately after yang reaches its extreme, one yin line begins to be born (hexagram Gou, the fifth lunar month in which the Summer Solstice falls). Within the very height of fullness, the seed of the turning point already lies hidden.
Daoist wisdom lies precisely in the ability to foresee "decline" within "flourishing," to foresee "deficiency" within "fullness," to foresee summer within spring's imminent end, to foresee the sprouting of yin within yang's imminent extreme. This forms a profound complement to the Confucian posture of "advancing"—seizing the rain to sow, striving to bring forth vitality: Confucianism teaches people to seize the rain and sow, expanding vitality (exerting effort in the direction of "growth"), while Daoism reminds people that fullness must reverse, that one should retire once one's task is accomplished (remaining clear-headed even amid "fullness"). One advancing, one withdrawing; one active, one still—these are precisely the two most balanced, most profound states of mind with which the Chinese people have faced this solar term of Guyu, "about to be full yet not yet full."
Section 5: "The Dao Models Itself on What Is Naturally So" — The Effortless Rightness of Guyu's Rain
The most central line of Daoist cosmology is the Most High's saying: "Humanity models itself on Earth; Earth models itself on Heaven; Heaven models itself on the Dao; and the Dao models itself on what is naturally so." (Daodejing, Chapter 25) This fourfold chain of modeling can be used precisely to illuminate the nature of Guyu's rain.
What does "the Dao models itself on what is naturally so" mean$1 "What is naturally so" (自然, ziran) does not refer to "Nature" in the sense of mountains, rivers, grasses, and trees, but rather means "being so of itself," "being so originally." The reason the Dao is the Dao is that it models itself on nothing higher; it simply operates, "being so of itself."
Let us apply this level of meaning to Guyu: the rain of Guyu falls in late spring, and coaxes forth precisely the hundred grains, not because anyone "commands" it to do so, nor because it "deliberately" intends to do so, but simply because the qi of Heaven and Earth, having run its course to this point, brings this rain down, "being so of itself." The rain does not force itself, does not contrive, does not calculate—it falls "naturally," moistens "naturally," and brings forth the hundred grains "naturally." This ease of "hitting the mark without effort, attaining without deliberation" is precisely the living manifestation, in a single spring rain, of "the Dao modeling itself on what is naturally so."
From here, let us turn back to "humanity models itself on Earth; Earth models itself on Heaven": at the season of Guyu, humanity should "model itself on Earth"—observing the earth's return to warmth, the sufficiency of soil moisture, the phenology of duckweed sprouting and mulberry greening, and accordingly sowing seed and gathering mulberry leaves with composure. This act of "modeling oneself on Earth," at its highest level, should likewise be "natural"—not a mechanical, rigid following of the calendar, going through the motions by rote, but rather a deep resonance of body and mind with the rhythms of the earth, so that one "knows," naturally and effortlessly, that it is time to sow, time to gather mulberry leaves—like the intuition, passed down through generations of farmers, of "watching the sky, watching the earth, watching the phenology."
The earth's return to warmth "models itself" on Heaven's northward movement (the sun moving north, the noon shadow gradually shortening); Heaven's movement, in turn, "models itself" on the Dao; and the Dao "models itself" on "what is naturally so." Thus, tracing back level by level from a single grain of seed being sown, to the earth's return to warmth, to the sun's northward journey, to the turning of the Dao, all ultimately return to that "being so of itself" which is "what is naturally so."
The rain of Guyu's moistening of things and its coaxing forth of the hundred grains appears, on the surface, to be a deliberate grace of Heaven and Earth (what Confucianism calls "the humaneness of Heaven and Earth"); yet in Daoist eyes, it is still more the great transformation—effortless yet unerring, being so originally—of "the Dao modeling itself on what is naturally so." Heaven and Earth do not "wish" to bestow grace; they simply operate "naturally," and the hundred grains are thereby "naturally" born.
These two interpretations—Confucianism's "deliberate humaneness" and Daoism's "natural transformation"—are precisely like the two faces of Guyu's rain: on one side, a warm and compassionate grace; on the other, an unminded, effortless great transformation. The two mirror each other, and only together do they reveal that deepest character of Guyu's rain—at once compassionate and transcendent.